There's a lot of confusion around peptides and muscle. Here's how I actually think about it. Most peptides don't build muscle directly. They improve the systems that allow muscle to grow. First, IGF 1 LR3 1MG Beverly Hills Rejuvenation Center Explanation, Benefits, and Dosing for IGF LR3 Wittmer Rejuvenation Clinic What Are the Best Peptides for Muscle Growth? The 7 Best Peptides for Muscle Growth IGF 1 LR3 does not promote growth in late gestation growth restricted fetal sheep American Journal of Physiology Endocrinology and Metabolism American Physiological Society